Metalliferous trisazo dyestuffs



United States Patent METALLIFEROUS TRISAZO DYESTUFFS -Heuri Riat, Arlesheim, Switzerland, assignor to Ciba Limited, Basel, Switzerland, a Swiss firm No Drawing. Application February 15, 1954,

Serial No. 410,440 7 7 Claims priority, application Switzerland February 26, 1953 10 Claims. (Cl. 260-447) I This invention provides metalliferous triazodyestuifs which, for example, like the dyestufi of the formula "ice Patented Jan. 29, 1957 be made in various ways,for example, a tetrazo compound of a diamine of the formula may be coupled on the one hand with a pyrazolone and on the other with a middle component O-Alkyl H-R2NH2) which contains an alkoxy group in ortho-position to the amino group, further diazotizing the resulting aminodisazo-dyestuff, and coupling the diazo-disazo-compound with an end component of the naphthalene series capable of coupling in a position vicinal to a hydroxyl group.

Furthermore, the amino-disazo-dyestuffs used as intermediate dyestufls and corresponding to the formula 7 in which Me represents a n ckel or copper atom bound in complex union, Y represents a CH=CH- group or a direct bond, Py represents a pyrazolone radical, R1 and R2 represent benzene radicals, R3 represents an aromatic radical containing at the most 10 aryl carbon atoms, viz. a benzene or naphthalene radical bound in paraposition to the azo-linkages, and R4 represents the radical of an end component of the naphthalene series, and in which the azo linkages bound to R1 and R2 are in paraposition relatively to Y and the -OMeO- group is connected to each of the radicals R3 and R4 in a position vicinal to the azo linkage.

The invention also provides a process for making the metalliferous dyestufis of the above general formula, wherein a trisazo-dyestuft' of the formula 50 in which the O--alkyl group is in ortho-position relatively to the -*N=NR4 group,

Y-represents a CH=CH-- group or a direct bond,

Py represents a pyrazolone radical,

R1 and R2 represent benzene radicals,

Ra represents a benzene or naphthalene radical bound in para-position to the azo linkages, and

R4 represents the radical of an end component of the naphthalene series containing a hydroxyl group in a position vicinal to the azo linkage and in which the azo linkages bound to R1 and R2 occupy para-positions relatively to Y, is treated with an agent yielding a metal having an atomic numberrranging from 28 to 29, viz. an agent yielding nickel or copper in such manner that an ortho:ortho-dihydroxy-metal complex is formed accompanied by the splitting oil? of the alkoxy group of ortho-hydroxy-ortho-alkoxy-grouping. The starting materials of the :Formula 3 preferably contain at least three sulfonic acid groups. They can can in some cases be made with advantage by diazotizing a compound of the formula in which one A represents a -NH2 group and the other A represents a substituent convertible into such group, for example, a nitro or acylamino group, and coupling the diazo compound with a pyrazolone, and then converting the said substituent into the NI-I2 group, diazotizing the amino-monoazo-dyestuff and coupling with a middle component. I

Furthermore, diamines of the Formula 4 which are diazotized on one side, when such diazo-compounds are accessible, may be coupled with pyrazolones, and then the resulting amino-monoazo-dyestufls are further diazotized and coupled with the middle components to form the amino-disazo-dyestuffs of the Formula 5. Another method for making the dyestuffs of the Formula 3 consists in diazotizing a compound of the Formula 6, cou pling the diazo compound with a middle component of the kind described above, further diazotizing the aminornonoazo-dyestufi so obtained, and coupling the diazw azo-compound with an end component of the naphthalene series capable of coupling in a position vicinal to a hydroxyl group, then converting the substituent A into the amino group, diazotizin'g and couplin with a pyrazolone.

As diamines of the Formula 4 there are used compounds which contain two benzene radicals bound to gether by a direct bond or'by a -CH===CH group,yeach of the benzene radicals containing an amino group as a substituent in para-position to Y. The benzene radicals acid groups. As examples there may be mentioned "the following diamines:

The above statements in connection with the diamines of the Formula 4 apply mutatis mutandis to the compounds of the Formula 6. As examples of the latter compounds there may be mentioned:

4-amino-4'-acetylaminodiphenyl, 4-amino-4-acetylaminodiphenyl-3-sulfonic acid and 4-nitro-4-aminostilbene-Z:2'-disulfonic acid.

Any desired pyrazolones may be used for preparing the starting dyestuffs. Thus, for example, there may be used 3-methyl-5 pyrazolone, 1-alkyl-3-methyl-5pyrazolone, and especially 1-phenyl-3-methyl-5-pyrazolone or a 1-ary1-3- methyl-S-pyrazolone of which the aryl radical may contain further substituents. As examples there may be mentioned .1-(4'-methylphenyl).-3-methyl 5 pyrazolone and 1-(4'- chlorophenyl)-3-methyl-5-pyrazolone. Pyrazolones which contain, advantageously in a phenyl radical bound in the 1-position of the pyrazolone ring, groups imparting solubility such, for example, as carboxylic acid groups, sulfonic acid groups or if desired sulfonic acid amide groups, are of special interest in the case of dyestuifs which would otherwise contain only a few groups imparting solubility. In this connection there may be mentioned as examples: l-phenyl-S-pyrazolone 3 carboxylic acid, 1-phenyl-3- rnethyl-5-pyrazolone-3'- or -4'sulfonic acid, 1-(4'-methylphenyl)-3-methyl-5-pyrazolone-3sulfonic acid, 1-(2- chlorophenyl)-3-methyl-5-pyrazolone 4' sulfonic acid, 1-phenyl-3-methyl 5 pyrazolone 4' carboxylic acid, 1-phenyl-5-pyrazolone-3-carboxylic acid-3-sulfonic acid and 1-pheny1-3-methyl- 5 pyrazolone-3'-sulfonic acid amide.

The middle components of the formula O-alkyl HRa-NH2 contain the --alkyl group, for example, an ethoxy group or advantageously a methoxy group capable of forming metal complexes in ortho-position to the amino group. There may be used the middle components of the benzene series and especially those of the naphthalene series such, for example, as 1-amino-2-methoxy-5-methylbenzene, 1-amino-Z-methoxybenzene, 1 amino 2:5 dimethoxybenzene, l-amino-Z:S-diethoxybenzene, 1-amino-2-methoxy-S-ethoxy benzene, l-amino 2 ethoxy-S-methoxybenzene, 1 amino 2 methoxynaphthalene, 1-amino-2- ethoxynaphthalene, l-amino-2-methoxynaphthalene-6-sulfonic acid, l-amino 2 methoxynaphthalene-7-sulfonic acid and 1-amino-2-ethoxynaphthalene-6- or 7-sulfonic acid.

As end components (H-R4) there came into consideration compounds of the naphthalene series capable of coupling in a position vicinal to a hydroxyl group, such as hydroxy-naphthalene sulfonic acids and especially amino-hydroxynaphthalene sulfonic acids containing substituted amino groups, 'for example, arylamino groups or acylamino groups. As examples there may be mentioned 2-hydroxynaphthalene, 2-hydroxynaphthalene-6-sulfonic acid, 2-hydroxynaphthalene-3 :6-disulfonic acid, 1-hydroxynaphthalene-4-sulfonic acid, 1-hydroxynaphthalene-3:6- or -3:8-disulfonic acid, 1 8-dihydroxynaphthalene-3 6-disulfonic acid, l-amino-S-hydroxynaphthalene-7-sulfonic acid, 1-amino-8-hydroxynaphthalene-4-sulfonic acid, Z-amino-5-hydroxynaphthalene-7-sulfonic acid, 2eamino-S-hydroxynaphthalene-6-sulfonic acid, Z-amino-6-hydroxynaphthalene-8-sulfonic acid, nitrogen-substituted Z-amino 5 hydroxynaphthalene-7- sulfonic acid such as 2-acetylamino-5-hydroxynaphthalene-7-sulfonic acid,

2-benzoylamino-5-hydroxynaphthalene-7-sulfonic acid,

2-(4' chlorobenzoylamino) 5 hydroxynaphthalene-7- sulfonic acid,

2-phenylamino-5-hydroxynaphthalene-7-sulfonic acid,

2-(2'- or 4-methoxypheny1amino)-5-hydroxynaphthalene- 7-sulfonic acid,

2-(3- or 4'-carboxymethoxyphenylamino)-5-hydroxynaphthalene-7-sulfonic acid,

2-(4-methylphenylamino) 5 hydroxynaphthalene-7:3-

disulfonic acid,

2-(4-chlorophenylamino) 5 hydroxynaphthalene-7:3-

disulfonic acid and Z-phenylamino 5 hydroxynaphthalene-7:3- or -7:4'-

disulfonic acid.

The dyestuffs of the Formula 3 can be made by the usual known methods. The tetrazotized diamines of the Formula 4 are advantageously coupled first in a weakly acid medium with the pyrazolone and then in a weakly acid to weakly alkaline medium with the middle component. Coupling with the end components is advantageously carried out in an alkaline medium and in the presence of pyridine or picoline.

As agents yielding metal for use in the process of the invention there come into consideration agents yielding nickel or advantageously agents yielding copper, and the treatment with the agent yielding metal is carried out in such manner that an ortho:ortho-dihydroxy-azo-copper complex is formed. Thus, for example, the metallization may be carried out with a salt of divalent copper or nickel in a weakly acid aqueous medium. However, the dyestuffs may be metallized by the method in itself known in which there is used a nickel or copper tetrammine complex in the presence or absence of an excess of an amine or ammonia, the metallization being advantageously carried out in an aqueous medium in the vicinity of C. for several hours. Of special advantage in some cases of this kind is the process of U. S. Patent No. 2,536,957, filed October 8, 1947, in which the metallization is carried out in the presence of a hydroxyalkylamine, especially ethanolamine, or a copper complex derived therefrom.

It is generally of advantage to copper dyestuffs of the general Formula 3, in which the radical R3 is a naphthalene radical, for example, dyestuffs in which the radical R3 corresponds to the formula I HOsS with copper sulfate with the addition of an alkali acetate.

On the other hand, it has been found advantageous to convert into ortho:ortho-dihydroxy-copper complexes with the aid of copper tetrammine sulfates those dyestuffs which contain at the aforesaid position in the molecule an alkoxy-benzene radical, for example of one of the formulae The metalliferous azo dyestufis of this invention are new and correspond to the above Formula -2. This forgreen dyeings of good fastness to light, which withstands an ordinary anti-creasing treatment, for example, by means of urea-formaldehyde resins. In dyeing cellulosecontaining materials by the usual direct dyeing methods other fibers, for example, fibers of cellulose esters, are not dyed,

The following examples illustrate the invention, the parts and percentages being by weight:

Example 1 26.4 parts of 4:4'-diaminodiphenyl 3-sulfonic acid are tetrazotized in the usual manner. After the addition of 40 parts of crystalline sodium acetate to the diazo-suspension, a neutral solution of 26 parts of 1-phenyl-3- methyl-5-pyrazolone-3'-sulfonic acid is run in. When the intermediate compound has been formed, the mixture is rendered neutral to Weakly alkaline with sodium carbonate, and coupling is carried out with a neutral solution of 25 parts of 1-amino 2-methoxynaphthalene-6-sulfonic acid. When the coupling is finished the disazo-dyestuff is separated, stirred into 1000 parts of water, and then diazotized at l015 C. by theaddition of 40 parts of concentrated hydrochloric acid and 7 parts of sodium nitrite. The diam-compound so obtained is then introduced into an ice cold solution of 28 parts of 2-acetylamino-5-hyclroxynaphthalene-7-sulfonic acid and 30 parts of anhydrous sodium carbonate in 3G0parts of water and 150 parts of pyridine (or picoline'L When the coupling is finished, the dyestufi. is salted out and filtered off.

The moist filter cake of the trisazo-dyestufi is dissolved in ZOGOparts of warm water. After the addition of 25 parts of crystalline sodium acetate and 25 parts of crystalline copper sulfate, the whole is heated for 10 hours at the boil under reflux. p

The copper complex formed is precipitated by the addition of 200 parts of sodium chloride, filtered and dried.

The dyestuff is a dark powder which dissolves in water i pling the diazo compound with the end component given in column III, and finally converting the trisazo-dyestutf so obtained into its orthofortho-dioxy-azo-copper complex:

I II III Tint of dyeingof thecop-.

Pyrazolone Middle com End component per component pound.

on cotton 1..... 1-phcnyl-3- 1-amin0-2- 2-benzoylaminoolive.

mcthyl-5- methoxy- 5-hydr0xynaphpyrazolo'ne-3- naphthalenethalene-7-sulsulfonic acid. ti-sulfonic acid. fontc acid.

2 ..d0 d0 l-benzoylamiuo- Do. I

8-hydroxynaphthalene- 4-sultonic acid.

3 ..d0 ..do Z-benzoylamino- Do.

. fi-hydroxynaphthalene- 8-sulfonic acid.

4 ..do d0 i-acetylamino s- Do.

. hydroxynaphthalene-4-sul- Ionic acid.

5 ..do .-do l-hydroxynaph- Do.

thal-ene-4-su1- ionic acid.

6 d0 ..do Z-hydroxynaph- Do.

thalene-G-sultonic acid. 7 ..d0 ..do 2-hydroxynaph- Do.

thalcne.

8..-. .....do 1-a1nino-2ethl-acetylamino- Do.

. oxynaphthas-hydroxylene=6-sulfon1c naphthaleneacid. 4-su1fonicac1d.

9 ..dc 1-aiuino-2-meth- Z-phenylaminogreenish oxvrmphtha- E-hydroxyolive. lene-G-sultonic naphthaleneacid. 7-sulf0nlc acid. 10.... 1-phenyl-3- ...do z-phenylarnino- Do.

methyl-5- fi-hydroxypyrazo1011e-=tnaphthalenesulfonic acid. 7-sulionic acid- 3-carbexyl ic acid.

11.... l-phenyl-S-pyv... do Z-acetylamino-S- grey.

razolone- 3- hydroxynaphcarboxyhc tha1ene-7 sulacid. ionic acid.

12.... l-pneuyl-fi-pydo Z-benzoylaminogreenish razolone 3- 5-hydroxygrey. carboxyhc naphthalenenc1d-3-sul- 7-sulfonic acid. ionic acid.

13.... 1-(4-methyld0.-.-...... Z-hydroxynapholive. phenyl)-3- thalene-fi-sulmethyl-5-pyfonlc acid. random-3- sultonic acid.

14... l(2-chlcro .....do.-.-....... l-hydroxynaph- D0. phenyD-3- thalcne-4-sulmethyl-5-pytonic acid. razoloue-4- sulfonic acid.

15-.-. l-phenyl-3 ....(lo 2-acetylamino-5- Do.

methyl-5-pyhydroxynaphrazo1one -4- thaIeneJ-sulcarboxylic acid ionic acid.

16.... l-phcnyl-S- 1-arnino-2-meizhl-hydroxynaph- Dc. methyl-F oxy-naphthathalene-4-sul razclonolcne. ionic acid. sulfonic ,id

17..-. 1-phenyl-3- l-aminmZ-meth- Z-acetylarnino-E- Do.

methyl-S-pyoxynaphthahydroxynaphrazolonc-4- lene-fi-sulionic thalene-7-sulsulfonic acid. acid. ionic acid.

18.... l-phenyl-B- l-amino-Z-moth- 2-benzoylalnino- D0.

methyl-.E-pyoxynaphtha-., 5-hydroxyraz0lone,3- lene-7-sulfonic naphthalene sulfonic acid. acid. 7-sultonic acid.

The dyestuffs Nos. 4, 5, following formulae:

c i--iouo rim-oc an 6and 17 correspond the SOaH 7 I I I on; I

HOaS

' SOaH Example 2 40 parts of'4-nitro-4-aminostilbene-Z:2-disulfonic acid are diazotized in the usual manner. The diazo-compound is coupled in the presence of sodium bicarbonate with 25 parts of 1-phenyl-3-methyl-S-pyrazolone-4'-sulfonic acid. The nitro group is reduced to the amino group at 35-40 C. with 42 parts of crystalline sodium sulfide, and the amino-azo-dyestuff is completely precipitated by acidification and admixture with sodium chloride, and filtered off. The dyestufi is diazotized in 1000 parts of water at Cpwith 30 parts of concentrated hydrochloric acid and 7 parts of sodium nitrite. The diazo-compound is filtered oif and added to a solution of 25 parts of 1- amino-2-methoxy-naphthalene-6-sulfonic acid, 4 parts of sodium hydroxide and parts of crystalline sodium acetate. After the coupling, the mixture is rendered alkaline with sodium carbonate and. heated to 90 C. By the addition of parts of sodium chloride to every 100 parts of solution the dyestuif is precipitated in an easily filterable form. It is then filtered off, stirred'in 1000 parts of water, acidified with parts of concen trated hydrochloric acid and diazotized at 10-15 C. with 8 parts of sodium nitrite dissolved in parts of water. The diazo compound is coupled with 28 parts of- Z-acetylamino-5-hydroxynaphthalene-7-sulfonie acid in a solution rendered alkaline with sodium carbonate in the presence of 150 parts of a mixture of pyridine bases. The trisazo-dyestutf is filtered off and Washed with sodium chloride solution of 5 percent strength.

The dyestuif paste is dissolved in 2000 parts of warm water, and mixed with a solution of 25 parts of crystalline copper "sulfate and 50 parts of an ammonia solution of 25 percent. strength. The whole is heated for 12 hours at 9095 C. under reflux, and the copper complex is isolated by the addition of sodium chloride followed by filtration. When dry, the resulting dyestuif is a dark powder which dissolves in water with an olive coloration and dyes cotton grey-olive tints which are fast Hoas-ON-o l HOa S ponent Z-benzoylarnino-5-hydroxynaphthalene-7-sulfonic acid and/or l-phenyl-3-methyl5-pyrazolone-3'- sulfonic acid, instead of 1-phenyl-3 methyl-S-pyrazolone-4'-sulfonic acid.

Example 3 30.6 parts of 4amino-4'-acetylaminodiphenyl-3-sulfonic acid are diazotized in the usual manner. The diazo compound is coupled with 26 parts of 1-phenyl-3-methyl-5- pyrazolone-4-carboxylic acid in a solution rendered alkaline with sodium carbonate. The acetyl group is then split off by heating with a sodium hydroxide solution of 4 percent strength, and the amino-azo-dyestufi is further diazotized, after neutralizing the excess of sodium hydroxide. The diazo-compound'is coupled in an acetic acid solution with 25 parts of 1-amino-2-methoxynaphthalene-6-sulfonic acid. The amino-disazo-dyestuff formed is separated, dissolved in water, acidified with 40 parts of concentrated hydrochloric acid, and diazotized at 1020 C. by the addition of 7 parts of sodium nitrite dissolved in 50 parts of Water. The diazo-compound is then coupled in a solution rendered alkaline with sodium carbonate and in the presence of 200 parts of pyridine with 28 parts of 2-acetylamino-5-hydroxynaphthalene-7- sulfonic acid. The trisazo-dyestuif is isolated, and converted into its copper complex by the method described in Example 1. The copper complex dyes cotton greenolive tints which are fast to light.

By using, instead of 2-acetylamino-S-hydroxynaphthalene-7-sulfonic acid, the corresponding quantity of Z-benzoylamino-5-hydroxynaphthalene-7-sulfonic acid or 1- hydroxynaphthalene-4-sulfonic acid, there are obtained dyessutfs having similar properties. i

By using, instead of l-phenyl-3-methyl-5-pyrazolone- 3'-sulfonic acid, 1-phenyl-3-methyl-5-pyrazolone there is obtained a dyestuif' which dyes cotton olive-green tints.

Finally, by using, instead of l-phenyl-3-methyl-5- pyrazolone 4 carboxylic acid, 1-pheny1-3-methyl-5-pyto light. razolone-3'-sulfonic acid there is obtained a dyestufl which 7 Similar dyestuifs are obtained by Using as end. comcorresponds to the formula 7 H025 N-O v l NHOO0H| 9 which possesses properties similar 'tOIthOSG of the dyestuff obtained as described in the first three paragraphs of Example 1.

Example 4 4' sulfonic acid in a solution rendered alkaline with sodium carbonate. After the coupling the mo-noazo-dyestuif is isolated and heated for 2 hours at 90 C. with a solution of sodium hydroxide of 4% strength for the purpose of splitting off the oxalic acid residue. The aminoazodyestufi is isolated, suspended in 1000 parts or" water. admixed with 7 parts of sodium nitrite and diazotized at 15 C. by rapidly adding 40 parts of concentrated hydrochloric acid. The diazo compound is filtered off, stirred in 1000 parts of water and after the addition of 30 :parts of sodium acetate is mixed with a neutral solution of 25 parts of 1-amino-2-methoxynaphthalene-6-sulfonic acid. After the coupling the disazo-dyestu'fi is separated and further diazotized. The 'diazo compound is coupled with 34 parts of Z-benzoylamino-S-hydroxynaphthalenc-7-sulfonic acid in a solution rendered alkaline with sodium carbonate and in the presence of 200 parts of pyridine. The dyestuff is isolated and converted into its copper complex by the method described in Example 2. After working up in the usual way a dark powder is obtained which dissolves in water with a violet-grey tint and dye cotton grey shades which are fast to light.

By using instead of l phenyl--pyralozone-3-carboxylic acid-4 sulfonic acid, 1phenyl-3-methyl-S-pyralozoneatsulfonic acid and instead of Z-benzoylamino-S-hydroxynaphthalene 7 sulfonic acid, 2acetylamine-hydroxynaphthalene-7-sulfonic acid there is obtained a dyestuff which dyes cotton olive tints.

if the final coupling in the above example is carried out with 28 parts of 2-acetylarnino-5-hydroxynaphthalenc- 7-sulfonic acid, there is obtained a dyestuff which possesses similar properties.

Example 5 The diazo compound from 30.6 parts of 4-arnino-4- acetyl-aminodiphenyl-3-sulfonic acid is coupled with 26 parts of 1-phenyl-5-pyrazo1one-3-carboxylic acid-4'sulfonic acid in a solution rendered alkaline with sodium carbonate. The monoazo-dyestuff is treated with a solution of sodium hydroxide of 4 percent strength until the acetyl group is completely split off. The resulting aminoazo-dyestuff is diazotized and the diazo compound is coupled with 13.7 parts of Iamino-2-methoxy-5-methylbenzene in an acetic acid medium. The disazo-dyestuff is isolated in an acid state and further diazotized, whereupon the diazo compound is entered into a solution of 28 parts of 2-acetylamino-5-hydroxynaphthalene-7-sulfonic acid, 30 parts of sodium carbonate and 50 parts of pyridine. After the coupling the dyestuif is isolated, dissolved in 2000 parts of water and mixed with a solution of 25 parts of crystalline copper sulfate and 100 arts of ammonia of 2-5' percent strength. The whole is heated for hours at 90-95 C. and the cupriferous dyestuff is isolated in the usual 'way. I It dissolves in water with a violet-grey color and dyes. cotton grey tints which are fast to light. i

A dyestufi with similar properties is obtained when 2- benz'oylarnino-5-hydroxynaphthalehe-7-sulfonic acid is used for the final coupling.

Example 6 100 parts of cotton are entered at 40 C. into 10 graphs of Example 1. Dyeing :is carried on for 'hour while the temperature is raised to C., 30 parts of crystalline sodium sulfate are added, and dyeing is continued for a further /2 hour at 9095 C. The cotton is then rinsed and dried. There is obtained an olive dyeing of very good fastness to light.

What is claimed is:

1. A metalliferous trisazo dyestuff containing at least three sulfonic acid groups and corresponding to the formula O---Me--0 P N:N-R1-Y RQ-N=N RQN=N-R4 in which Me represents a metal having an atomicnumber ranging from 28 to 29 and being bouiid i'n complex union, R1-Y-R2-- represents a member selected from the group consisting of radicals of the formulae i l 803E H038 and z z 3 G wherein one Z represents a hydrogen atom and the other Z represents a sulfonic acid group, Py represents a pyrazolone radical, R3 represents an aromatic radical containing at the most 10 aryl carbon atoms and carrying both azo groups attached thereto in para-position to one another, and R4 represents the radical of an end component of the naphthalene series, and in which formula the azo linkages bound to R1 and R2 are in para-position relatively to Y and the -O-Me-O- group is connected to each of the radicals R3 and R4 in a position vicinal to the azo linkage.

2. A metalliferous trisazo dyestuif containing at least three sulfonic acid groups and corresponding to the formula in which Me represents a metal atom having an atomic number ranging from 28 to 29 and bound in complex union, one Z represents a hydrogen atom and the other Z represents a sulfonic acid group, Py represents the radical of a l-phenyl-S-pyrazolone bound. to the azo linkage in its 4-position, R3 represents an aromatic radical containing at the most 10 aryl carbon atoms and carry ing both azo groups attached thereto in para-position to one another, and R4 represents the radical of an end component of the naphthalene series, and in which formula the azo linkages bound to R1 and R2 are in paraposition relatively to Y and the OMeO group is connected to each of the radicals R3 and R4. in a position vicinal to the azo linkage.

3. A metalliferous trisazo dyestufli containing at least three sulfonic acid groups and corresponding to the formula the naphthalene series, and in which formula the p -O----Cu-O group is connected to each of the radicals R3 and R4 in a position vicinal to the azo linkage.

41. A metalliferous trisazo dyestufi containing at least three sulfonic acid groups and corresponding to the formula 5. A metalliferous trisazo dyestufi of the formula in which one Z represents a hydrogen atom and the other Z represents a sulfonic acid group and R4 represents the to each of the radicals R3 and R4 in a position vicinal to 25 the azo linkage.

20 radical of an end component of the naphthalene series containing a sulfonic acid group and to which radical the azo group and the -O-Cu0 group are attached in adjacent position.

6. The metalliferous trisazo dyestuff of the formula H033 HOaS 7. The metalliferous trisazo dyestuff of the formula SOaH O SO35: 8. The metalliferous trisazo dyestufi of the formula On (I) Brigg 303B 9. The rnetalliferous trisazo dyestutf of the formula HOaSON-G I 1 l I 7 Ho3s- 7 zen-oo-crn CH3 I 110 8 I 10. The metalliferous trisazo dyestufi of the formula H038 7 r O---Cu-O N-O I 7 H038 NHVO O-CH= V (3Ha v 

1. A METALLIFEROUS TRISAZO DYESTUFF CONTAINING AT LEAST THREE SULFONIC ACID GROUPS AND CORRESPONDING TO THE FORMULA 